Add include dir to path to help compiling on suse
Merge branch 'master' into ser
Make type of item (was char) into it's own class.

Makes use of the type easier and will allow future expansion of this class.
Move add_padding out of destructors again.

For some reason it makes a difference whether add_padding() is called
"manually" or from the destructor of some of the Builder children. I added
lots of asserts trying to find the problem, but I can't figure it out.